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Could the remains of a 'dead' comet still be in the solar system? Astronomers are still searching 6 years later
一颗预计将接近地球的彗星在内太阳系剧烈解体五年后，其命运仍然是个谜。
Why does the moon look larger when it's on the horizon?
当月亮接近地平线时，它看起来很大——为什么呢？
